Electrical regulator.



A. A. TIRRILL.

ELECTRICAL REGULATOR.

APPLICATION FILED mm. 3. 1.914.

1 ,1 92,708. Patented July 25, 1916.

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MXQZMMLL UNITED STATES PATENT OFFICE.-

ALLEN A. TIBRILL, OF PITTSBURGH, PENNSYLVANIA, A$IGNOB TO WESTINGHOUSEELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENN SYLVAN IA.

ELECTRICAL REGULATOR.

Specification of Letters Patent.

Patented July 25, 1916.

To all whom it may concern:

Be it known that I, ALLEN A. TIRRILL, a citizen of the United States,and a resident of Pittsburgh, in the county of Allegheny and State ofPennsylvania, have invented a new and useful Improvement in Electricallegulators, of which the following is a specification.

My invention relates to electrical regulators of the kind in which theregulation is effected by opening andclosing a shunt circuit to aresistance in series with the field magnet winding of an exciter orother dynamo-electric machine.

The object of my invention is to provide Fig. 2 is a diagrammaticillustration of a modification of the system of Fig. 1.

The system illustrated, which is only one of many in which the presentinvention may be employed, comprises a generatorl that supplies currentto a distributing circuit 2 34, and that is provided with a field magnetwinding 5. The field magnet winding 5 is supplied with currentfromexciter bus bars 6-7, to which is connected an excit-er 8 having ashunt field magnet winding 9 and opposing auxiliary field magnetwindings 10 and 11, the former being arranged to supplement the shuntfield magnet winding 9, and the latter to oppose it. The field magnetwindings 10 and 11 are supplied with current from a storage battery 12,or they may be connected to any other suitable source, and suitablevariable resistors 13 and 14 are respectively connected in seriestherewith.

The resistors 13 and 14 are divided into a plurality of sections bymeans of leads or taps 15 and 16 that are respectively connected to thecontact terminals of two sets of relays 17 and 18, which serve toconnect and disconnect the said taps or leads, and to thereby establishshunt circuits to the resistors for the urpose of varying theireffective values. 'le only two rela s are included in each set,obviously a arger number may be employed if desired, or if condltionsdemand them. The relays 17 and 18 are respectively provided withenergizmg windings 19 and 20 to which current 1s supplied from thebattery 12 or any other suitable source.

The circuits of the windings 19 and 20 are respectively controlled bytwo other relays 21 and 22 having energizing windings 23 and 24,respectively, that are also supplied with current from the battery 12 oranother suitable source. The relay 21 com-prisesa movable contactterminal 25 and a s'tation ary terminal 26 that is placed below it andis adapted to cooperate therewith. In the relay 22, however, thestationary contact terminal 27 is mounted above the movable terminal 28.Because of this arrangement, the contact terminals of the relay 21 arecaused to engage, while those of the relay 22 are caused to disengagewhen the windings 23 and 24 are energized.

The circuits of the relay windings 23 and 24 are governed by a pair ofcooperating contact members 30 and 31, respectively, the

former of which is resiliently mounted, as,

for instance, by being placed upon the free end of a plate spring 32,and the other of which is mounted upon a depending arm of a lever 33.The lever 33 is pivotally supported at the lower end of the vertical armof a bell crank lever 34 and is actuated by an electromagnet com-prisinga core 35 and a solenoid 36 that is supplied with current proportionalto the voltage of the distributing circuit 234. The position of the anyother desired electrical condition of a circuit.

The, lever 34 is actuated by an electromagnet comprising a core 37 and asolenoid 38 that is supplied with current from the distrib'utin circuit2-34 but that may be supplie from any other suitable source of current,a resistor 29 being connected in series with the winding 38. A shuntcircuit to the resistor 29 is adapted to be opened and closed by meansof a relay 39 having an energizing winding 40 that is connected inparallel with the windings 23 and 24, and the circuit of which issimilarly controlled by the contact members 30 and 31.

The relay 39 causes" the winding 38 to be alternately fully andpartially energized with the result that the contact terminal 31 isvibrated into and out of engagement with the terminal 30. The periods ofengagement and disengagement of the said members depend upon the initialdistance between, or the relative positions of, the contact terminals 30and 31 as determined by the coil 36.

In the operation of the regulator, the engagement and disengagement ofcontact terminals 30 and 31, which takes place as above described,serves to close and open the circuits of the relay windings 23, 24 and40. The efi'ect of opening and closin the circuit of the winding 40 hasalrea y been described. When the relay windings 23 and 24 are energized,the contact terminals 25 and 26 are caused to engage, while the contactterminals 27 and 28 are caused to disengage. The windings 19 of therelay 17 are, accordingly, energized, and the resistor 13 in the circuitof the auxiliary field magnet winding 10 is short circuited. Theauxiliary winding 10 then becomes more strongly energized than thewinding 11, and, being arranged to assist the main field magnet winding9, the voltages of the eXciter and generator are correspondinglyincreased. On the other hand, when the relay windings 23 and 24 aredeenergized, the contact terminals 25 and 26 are caused to disengage,and the terminals 27 and 28 to engage. The circuits of the win 's 20 ofthe relays 18 are thereby established, and the resistor 14 in thecircuit of the auxiliary field magnet winding 11 is short circuited. Thewinding 11 then predominates over the winding 10, and, being arranged tooppose the winding 9, the voltages of the exciter and generator arecorrespondingly reduced. The relation of the periods of engagement anddisengagement of the contact terminals 30 and 31, which is determined bythe voltage of the distributing circuit, also determines the relation ofthe periods during which the resistors 13 and 14 are short circuited,the arrangement being such that the regulator operates to maintain thevoltage of the circuit 2-3-4 substantially uniform, notwithstandingconsiderable variations of load upon the circuit.

The employment of two relays 21 and 22 for the purpose of governing theshunt circuits to the exciter field resistors 13 and 14, permits ofseparate adjustment of the relations of the contact terminals that arerespectively associated with said'resistors to compensate for wear andto give the most desirable conditions of operation. Since the two setsof terminals may wear unequally, and since one relay may be required tooperate under different conditions from the other, this independence ofadjustment is particularly advantageous, and results in greaterefiectiveness and reliability of-operation of the regulator.

In Fig. 2, I have shown a modification of a portion of the system ofFig. 1 in which a single auxiliary field magnet winding 43 is providedfor the exciter, one terminal of which is connected to the middle oranother suitable intermediate point of the battery 42, and the remainingterminal is connected through resistors 45 and 46 to the respectiveterminals of the battery. A resistor 47 is included in the connection ofthe winding 43 to the middle point of the battery, and other resistors48 and 49 are connected in series with the resistors 45 and 46 so that,in case the latter resistors become permanently short-circuited, thebattery cannot be short-circuited.

I claim as my invention:

1. The combination with a dynamo-electric machine having opposing fieldmagnet windings, of a regulator comprising c0- operating contactmembers, a winding for causing said contact members to engage anddisengage, three relays controlled by said contact members, one of whichin turn controls the circuit of the said regulator winding, and theother two of which respectively control the energization of said fieldmagnet windings.

2. The combination with a dynamo-electric machine having opposing fieldmagnet windings, of a regulator comprising cooperating contact members,a winding for causing said contact members to engage and disengage,three relays controlled by saidcontact members, one of which in turncontrols the circuit of the said regulator winding, and the others ofwhich respectively and oppositely control the energization of said fieldmagnet windings.

In testimony whereof, I have hereunto subscribed my name this 20th dayof Feb. 1914.

ALLEN A. TIRRILL.

Witnesses:

Orro S. SCHAIRER, B. B. HINES.

